Research under this project will be carried out along the following main lines of investigation: a. To determine the site of formation of collagen and hyaluronic acid in the vitreous and the mechanism by which the liquid vitreous develops in humans. Further confirmation for the pathway of disappearance of HA will be sought. b. The antiinflammatory and tissue regeneration regulating the effect of hyaluronic acid in the vitreous, anterior chamber, iris and ciliary body will be studied. c. The conformation of hyaluronic acid in solution will be studied and the correlation between conformation (double helical content) and biological activity (interaction with cell surface) will be explored.